Green MP Sue Kedgley has confirmed her retirement at the next election.

Kedgley, known for her advocacy on food safety and animal welfare, is among the original group of Green MPs who first entered Parliament 1999, of which only she and Keith Locke remain.

The four term MP said she would keep her "foot on the accelerator" between now and the election as there was still a lot of unfinished business.

"My Animal Welfare Amendment Bill will be debated in Parliament shortly, our report on the state of the aged care will be released next month, and I will be releasing a member's bill calling for a supermarket code of conduct."

Ms Kedgley said she announced her decision today as the Green Party's Wellington Central electorate is in the process of selecting its candidate for 2011.